4.2 INTERMOLECULAR FORCES

C-Cl and C-Br both have dipole dipole forces. However, one of them will exhibit stronger dipole dipole forces than the other. Which one is it and why? a. C-Br because there is a larger electronegativity difference b. C-Br because there is a smaller relative electronegativity difference c. C-Cl because there is a smaller relative electronegativity difference d. C-Cl because there is a larger electronegativity difference

C-Cl because there is a larger electronegativity difference

If CH4 and C2H6 both have only London Dispersion Forces, which one would have stronger attraction and why? C2H6 because it can also form hydrogen bonds C2H6 because it has a higher molar mass CH4 because it would have lower vapor pressure

C2H6 because it has a higher molar mass

If CH4 and C2H6 both have only London Dispersion Forces, why does C2H6 have a higher melting point? C2H6 has less LDFs because of its higher molar mass C2H6 has a stronger LDFs because it has a higher molar mass CH4 has a lower molar mass so it would have stronger intermolecular forces

C2H6 has a stronger LDFs because it has a higher molar mass

Comparing the following molecules, CH4, H2S, and HF, which of the following would have the highest vapor pressure? H2S HF CH4

CH4

Comparing the following molecules, CH4, H2S, and HF, which of the following would have the highest melting point? H2S CH4 HF

HF

Which of the following has the highest vapor pressure/volatility? dipole dipole hydrogen bonding LDFs

LDFs

Which of the following is true of London Dispersion Forces/Van der Waals forces? Choose all that apply + LDFs are the weakest intermolecular force + polar molecules contain LDFs + nonpolar molecules contain LDFs + LDFs are the strongest intermolecular force

LDFs are the weakest intermolecular force polar molecules contain LDFs nonpolar molecules contain LDFs

A substance with a higher molar mass has stronger LDFs True False

True: there are more electrons to move around (more electrons allows a higher chance for a temporary dipole to be formed).

Compare H2O vs. CH3OH. Both have hydrogen bonds. Which substance has stronger intermolecular forces and why? a. CH3OH has stronger intermolecular forces because it can create more hydrogen bonds b. H2O has stronger intermolecular forces because it has a lower molar mass c. H2O has stronger intermolecular forces because it can create more Hydrogen bonds d. CH3OH has stronger intermolecular forces because it can create less hydrogen bonds

c. H2O has stronger intermolecular forces because it can create more Hydrogen bonds

intermolecular force

forces of attraction between multiple molecules

intramolecular force

forces of attraction within just one molecule

Which of the following has the highest melting point/boiling points? a. dipole dipole b. hydrogen bonding c. LDFs

hydrogen bonding

What type of molecules form hydrogen bonds? a. all polar molecules b. only polar molecules with O-H, F-H, or N-H bonds c. nonpolar molecules

only polar molecules with O-H, F-H, or N-H bonds